Why in the News?
Two alien planets about 218 light years away from Earth have found a twin in the ocean worlds of Europa and Enceladus- moons orbiting Jupiter and Saturn.
Key findings
- The exoplanets, Kepler-138 c and Kepler-138 d, are likely water worlds, a feature that scientists have theorised for a long time.
- These twin planets of the same size and mass are more massive than Earth but lighter than ice giants Uranus and Neptune.
- They are different from the planets in our solar system, which is chiefly composed of rocky planets like Earth and gas giants like Jupiter.
- The Kepler- 138 c and d are made up of ingredients lighter than rock (rocky planets like Earth) but heavier than hydrogen or helium (gas-giant planets like Jupiter).
- The new planet takes 38 days to complete an orbit.
- It is in the habitable zone, meaning it is located in an orbit that receives just the right amount of heat from its star to allow water to exist in a liquid form.
Q1) What are exoplanets?
Exoplanets are planets that orbit a star other than the sun.These worlds are far outside our own solar system. Astronomers have confirmed more than 5,000 exoplanets orbiting distant stars.
Source: Down to Earth
Last updated on Sep, 2026
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